Delivery system and method for interstitial radiation therapy using seed strands constructed with preformed strand housing

Abstract

A delivery system and method for interstitial radiation therapy comprising substantially axially stiff and radially flexible elongated members made of material which is bioabsorbable in living tissue and a plurality of radioactive seeds dispersed in a predetermined array within the elongate member. The radioactive seeds can be dispersed within assembled half-shells made of the same material. The housing for the radiation seeds can also be manufactured from extruded material. A system for manufacturing the interstitial radiation therapy seed strands that automatically makes the seed strands is also provided. The delivery system and method further customize the member based on a prescription.

What is claimed is:  
     
       1. A therapeutic element comprising: 
       first and second elongate half-shell members;  
       radioactive seed elements;  
       wherein said radioactive seed elements are dispersed between said first and second elongate members, and  
       said first and second elongate half-shell members are join to form an elongate member to hold said radioactive seed elements.  
     
     
       2. The therapeutic element of  claim 1  wherein spacers are interspersed with said radioactive seed elements. 
     
     
       3. The therapeutic element of  claim 1  wherein one or both of said elongate half-shell members are impregnated with a drug. 
     
     
       4. The therapeutic element of  claim 1  wherein drug impregnated seed elements are interspersed with said radioactive seed elements. 
     
     
       5. The therapeutic element of  claim 1  wherein one or both of said elongate half-shell members are impregnated with a hormone. 
     
     
       6. The therapeutic element of  claim 1  wherein hormone impregnated seed elements are interspersed with said radioactive seed elements. 
     
     
       7. The therapeutic element of  claim 1  wherein a polymer is flowed into the spaces between said first and second elongate members and said radioactive seed elements. 
     
     
       8. The therapeutic element of  claim 1  wherein elongate half-shell members have pre-shaped indentations for said radioactive seed elements. 
     
     
       9. The therapeutic element set forth in  claim 1  herein said first and second elongate half-shell members meet to form an tube that contains said radioactive seed elements. 
     
     
       10. The therapeutic element set forth in  claim 1  wherein said first and second elongate half-shell members meet to form an tube that contains said radioactive seed elements and said tube is heated to mold tightly around said radioactive seeds. 
     
     
       11. The therapeutic element set forth in  claim 1  wherein said elongate half-shell members assembled with seed elements are axially rigid and radially flexible. 
     
     
       12. The therapeutic element set forth in  claim 1  wherein said elongate half-shell members are sufficiently axially rigid to prevent jamming or collapsing while being pushed out of a needle. 
     
     
       13. The therapeutic element set forth in  claim 1  wherein said elongate half-shell member has sufficient radial flexibility to maintain locational accuracy relative to a tumor target as said tumor target shrinks in size. 
     
     
       14. The therapeutic element set forth in  claim 1  wherein the thickness of said elongate half-shell members around said radioactive seeds is sufficient to decrease normal tissue necrosis from a high local dose of radiation. 
     
     
       15. The therapeutic element set forth in  claim 1  wherein said radioactive seed elements are positioned at various intervals along the length of said elongate half-shell members. 
     
     
       16. The therapeutic element set forth in  claim 1  wherein said radioactive seeds contain an isotope consisting of the group iodine  125 , palladium  103 , iridium  192 , cesium  131 , gold  198  yttrium  90  and phosphorus  32 . 
     
     
       17. The therapeutic element set forth in  claim 1  wherein said elongate half-shell members are composed of a bioabsorbable material. 
     
     
       18. The therapeutic element set forth in  claim 1  wherein said elongate members are composed of a bioabsorbable material absorbed by living tissue within about 70 to 120 days. 
     
     
       19. The therapeutic element set forth in  claim 1  wherein said elongate half-shell members are composed of absorbable material selected from the group consisting of polymers and copolymers of glycolide, lactide and polydiaxanone. 
     
     
       20. The therapeutic element set forth in  claim 1  wherein said elongate half-shell members are echogenic. 
     
     
       21. The therapeutic element set forth in  claim 1  wherein said elongate half-shell members have air bubbles. 
     
     
       22. The therapeutic element of  claim 1  wherein said members have a durometer in the range of about 20 to about 80. 
     
     
       23. The therapeutic element of  claim 1  wherein said members have a durometer in the range of about 20 to about 40. 
     
     
       24. The therapeutic element set forth in  claim 1  wherein said elongated half-shell members are composed of a bioabsorbable material which is absorbed when the half-life of the radioactive seed elements is reached. 
     
     
       25. The therapeutic element of  claim 1  wherein said therapeutic element is steam sterilizable. 
     
     
       26. The therapeutic element of  claim 1  wherein the radioactive seed element is bioabsorbable. 
     
     
       27. The therapeutic element of  claim 1  wherein the radioactive seed element also contains a drug and wherein the seed element is bioabsorbable. 
     
     
       28. A device to be used with therapeutic seeds in order to assembly a therapeutic element, which device comprises: 
       a first elongated half-shell having a half-bore adapted for receiving the therapeutic seeds;  
       a second elongated half-shell having a half-bore which can mate with the first elongated half-shell in order together to define a full bore that is adapted to contain the therapeutic seeds; and  
       wherein said first and second elongated half-shells are made of a biocompatable, and bioabsorbable material.  
     
     
       29. The device of  claim 28  wherein said device is echogenic. 
     
     
       30. The device of  claim 28  wherein said device contains one of a drug and a hormone. 
     
     
       31. The device of  claim 28  wherein said device is capable of being heated in order to have the first and second elongated half-shells fuse together. 
     
     
       32. The device of  claim 28  wherein said device has a durometer in the range of 20 to 80. 
     
     
       33. The device of  claim 28  wherein said device has a durometer in the range of 2 to 40. 
     
     
       34. The device of  claim 28  wherein at least one of said half-shells has indentations adapted for receiving seeds. 
     
     
       35. The device of  claim 28  wherein said half-shells are bioabsorble in a mammal in less than one year. 
     
     
       36. The device of  claim 28  wherein said second half-shell has indentations adapted for receiving seeds. 
     
     
       37. The device of  claim 28  wherein said half-shells are bioabsorble in a mammal in less than one year. 
     
     
       38. A device to be used with therapeutic seeds in order to assembly a therapeutic element, which device comprises: 
       a first elongated half-shell having indentations adapted for receiving the therapeutic seeds;  
       a second elongated half-shell which can mate with the first elongated half-shell in order together to contain the therapeutic seeds; and  
       wherein said first and second elongated half-shells are made of a biocompatable, and bioabsorbable material.  
     
     
       39. The device of  claim 38  wherein said device is echogenic. 
     
     
       40. The device of  claim 38  wherein said device contains one of a drug and a hormone. 
     
     
       41. The device of  claim 38  wherein said device is capable of being heated in order to have the first and second elongated half-shells fuse together. 
     
     
       42. The device of  claim 38  wherein said device has a durometer in the range of 20 to 80. 
     
     
       43. The device of  claim 38  wherein said device has a durometer in the range of 20 to 40. 
     
     
       44. The device of  claim 38  wherein said second half-shell has indentations adapted for receiving the seeds. 
     
     
       45. The device of  claim 38  wherein said second half-shell has a half-bore. 
     
     
       46. A therapeutic element comprising: 
       first and second elongate half-shell members made of polymeric material;  
       a plurality of therapeutic seed elements; wherein  
       said plurality of therapeutic seed elements are placed between said first and second half-shell members, and  
       said first and second elongate half-shell members are joined and form an elongated member by encapsulating said plurality of radioactive seed elements.  
     
     
       47. The therapeutic element of  claim 46 , wherein 
       said first and second half-shell members are joined by heating the polymeric material.  
     
     
       48. The therapeutic element of  claim 46 , wherein 
       at lease one elongated half-shell member has indentations adapted for receiving the therapeutic seeds.  
     
     
       49. The therapeutic element of  claim 46  wherein the polymeric material is a polymer. 
     
     
       50. The therapeutic element of  claim 46 , wherein 
       said first and second half-shell members have reciprocal joining parts, and  
       forms said elongated member by.  
     
     
       51. The therapeutic element of  claim 46 , wherein said first and second elongate half-shell members are joined by heating at least one half-shell member. 
     
     
       52. The therapeutic element of  claim 46 , wherein the polymeric material is a co-polymer. 
     
     
       53. The therapeutic element of  claim 46  wherein the polymeric material is a natural bio-compatible material. 
     
     
       54. The therapeutic element of  claim 46  wherein the polymeric material is a synthetic bio-compatible material. 
     
     
       55. The therapeutic element of  claim 46  wherein the polymeric material is a natural bio-absorbable material. 
     
     
       56. The therapeutic element of  claim 46  wherein the polymeric material is a synthetic bio-absorbable material. 
     
     
       57. The therapeutic element of  claim 46  wherein the elongated member has alternating segments of polymeric material and seed elements. 
     
     
       58. The therapeutic element of  claim 46  wherein the elongated member is axially rigid and radially flexible. 
     
     
       59. The therapeutic element of  claim 46  wherein the elongated member has a substantially constant diameter. 
     
     
       60. The therapeutic element of  claim 46  wherein the elongated member has a diameter substantially similar to the diameter of the radioactive seed elements. 
     
     
       61. The therapeutic element set forth in  claim 46  wherein said elongate member is sufficiently rigid axially to prevent jamming or collapsing while being pushed out of a needle. 
     
     
       62. The therapeutic element set forth in  claim 46  wherein said elongate solid member has sufficient radial flexibility to maintain locational accuracy relative to a tumor target as said tumor target shrinks in size. 
     
     
       63. The therapeutic element set forth in  claim 46  wherein the thickness of said elongate solid member around said radioactive seeds is sufficient to decrease normal tissue necrosis from a high local dose of radiation. 
     
     
       64. The therapeutic element set forth in  claim 46  wherein said elongate solid member is longitudinally flexible. 
     
     
       65. The therapeutic element set forth in  claim 46  wherein said polymeric material is impregnated with a hormone. 
     
     
       66. The therapeutic element set forth in  claim 46  wherein said polymeric material is impregnated with a drug. 
     
     
       67. The therapeutic element set forth in  claim 46  wherein said radioactive seed elements are positioned at various intervals along the length of said elongate solid member. 
     
     
       68. The therapeutic element set forth in  claim 46  wherein said radioactive seed elements are impregnated with a hormone. 
     
     
       69. The therapeutic element set forth in  claim 46  wherein said radioactive seed elements are impregnated with a drug. 
     
     
       70. The therapeutic element set forth in  claim 46  wherein said radioactive seeds contain a compound or element that emits photonic radiation having a low energy and a short half-life. 
     
     
       71. The therapeutic element set forth in  claim 46  wherein said radioactive seeds contain an isotope consisting of the group iodine  125 , palladium  103 , iridium  192 , cesium  131 , gold  198  yttrium  90  and phosphorus  32 . 
     
     
       72. The therapeutic element set forth in  claim 46  wherein said polymeric material is absorbed by living tissue within about 70 to 120 days after implant. 
     
     
       73. The therapeutic element set forth in  claim 46  wherein said polymeric material is absorbed by living tissue at substantially the same time as the half-life of the radioactive seed elements are reached. 
     
     
       74. The therapeutic element set forth in  claim 46  wherein said polymeric material is selected from the group consisting of polymers and copolymers of glycolide, lactide and polydiaxanone. 
     
     
       75. The therapeutic element set forth in  claim 46  wherein said elongate solid member is echogenic. 
     
     
       76. The therapeutic element set forth in  claim 46  wherein said elongate solid member has air bubbles dispensed within. 
     
     
       77. The therapeutic element of  claim 46  wherein said elongate member has a durometer in the range of about 20 to about 40. 
     
     
       78. The therapeutic element of  claim 46  wherein said elongate member has a durometer in the range of about 20 to about 80. 
     
     
       79. The therapeutic element of  claim 46  wherein said polymeric material is moldable during manufacture of the therapeutic element. 
     
     
       80. The therapeutic element of  claim 46  wherein said polymeric material forms said elongated member through compression molding techniques.